Irish people are being exposed to higher levels of radiation than previously estimated, according to a new report.
The findings have shown that the most recent estimate of the radiation dose received by the Irish population shows a 9% increase over previous estimates.
The report, Radiation Doses Received by the Irish Population, published by the Radiological Protection Institute of Ireland (RPII), is based on a three-year study of the various sources of radiation to which Irish people are exposed, which includes both natural and artificial radiation.
Natural radiation includes radon, a naturally occurring radioactive gas present in all rocks and soils, thoron, a radioactive gas similar to radon and cosmic radiation from outer space. Artificial sources include dental and medical exposure, for instance via X-rays, discharges from Sellafield and the accident at Chernobyl.
The report states that on average, a person in Ireland receives an annual dose of 3,950 µSv (microsieverts) from all sources of radiation. This is equivalent to about 200 chest X-rays per person per year. In the UK, this figure is 2,600 µSv, while the world-wide average is 2,800 µSv.
According to the report, the primary source of radiation in Ireland is radon. When radon surfaces in the open air, it is quickly diluted to harmless concentrations. However when it enters an enclosed space such as a house, it can sometimes build up to high concentrations, leading to an ‘unacceptable health risk’.
‘Radon is a cancer causing gas and is the second most important cause of lung cancer in the country. It is also one of the few sources which can be controlled through measurement and remediation, both of which are relatively inexpensive to undertake,’ explained the report’s main author, Dr Tony Colgan of the RPII.
The report identifies medical exposure to radiation as a matter of potential concern.
‘In recent years, several countries have experienced a very significant increase in the radiation exposure of patients. Many of the new diagnostic techniques now available routinely deliver relatively high radiation doses and it is important that each exposure is fully justified,’ Dr Colgan said.
According to the findings, the radiation doses in Ireland that are attributable to discharges from the Sellafield reprocessing plant are low compared to other sources of radiation exposure. Ongoing monitoring has shown that these discharges and the associated radiation doses in Ireland have been continuously reduced since the 1970s and early 1980s.
‘For those who eat fish and shellfish from the Irish Sea, their radiation doses are of negligible health significance and the RPII does not recommend any restrictions on the consumption of seafood landed at east coast ports,’ Dr Colgan added.
The report shows that overall, 86% of the average radiation dose in Ireland comes from natural sources, while medical exposure accounts for the bulk of exposure from artificial sources.
For more information on radiation, radon and the RPII, visit www.rpii.ie.